Biocompatible membranes can be prepared by several different methods. In one method, purified collagen fibers extracted from collagen-rich tissues (e.g., tendon and dermis) are used to reconstitute a membrane, as described in U.S. Pat. Nos. 6,391,333; 6,599,524; and 7,807,192. An alternative method relies on the use of a tissue-derived membrane (e.g., pericardium, peritoneum, and small intestine submucosa) as a starting material, as described in U.S. Pat. Nos. 5,837,278 and 5,993,844.
Tissue-derived membranes such as pericardium and peritoneum typically contain two sides. The side that is in contact with internal organs and body fluid is known as the visceral, or serous, layer, while the side that is in contact with the abdominal or heart walls is termed the parietal layer. The visceral layer, which is smooth, does not adhere to adjacent body tissue. By contrast, the parietal layer is integrated with the tissue adjacent to it. The parietal layer must be mechanically separated from the adjacent body wall tissue in order to remove a tissue-based membrane from the body. The parietal layer of a tissue-based membrane torn from the integrated soft tissue of the body wall is covered with fibrous material. This fiber-covered surface of the parietal layer is adhesive, favoring cell adhesion and tissue growth. The fibrous material on the parietal side of membranes isolated from animals can be easily identified under microscopy, such as scanning electron microscopy.
Biocompatible membranes are often used in medical and dental surgeries. At times, it is necessary to use a membrane that is not adhesive on either side so as to avoid any adhesion to the surrounding tissue. For example, a non-adhesive membrane can be used for surgical repair of torn dural membranes, as well as for dental surgery requiring guided tissue repair.
The need exists for a tissue-based biocompatible membrane that can be used in situations where cell adhesion to the membrane is undesirable.